Given that there is the Description element for "annotating" a JSDL document, I think that JobAnnotation's semantics are
 too vague. I think that if JobAnnotation is specified, then it MUST be understood (i.e. the contents of the element) by
 the consuming system. 

Otherwise, I'd like some clarification on how this element is to be used in some examples. That is, an example of a 
JobAnnotation that MAY or MAY NOT be understood.